1. Field of the Invention
This invention relates to information retrieval systems, and more particularly to wireless information retrieval systems employing flexible display screens.
2. Description of the Related Art
The Internet provides a rich repository of information, and search tools are available for finding information quickly. However, such information can generally be accessed only by a computing element such as a desktop, laptop, personal digital assistant, PDA, or cell phone. The desktop and laptop typically have medium size display screens that make viewing comfortable and convenient, but they take several minutes to set up in an operating condition. Sometimes they occupy too much desk space in a home or office environment. PDAs and cell phones typically have smaller screens that severely limit the amount of information that can be displayed, but they are easier to carry and quicker to deploy.
Tuners for receiving radio and television signals have been available for many decades. Both visual and aural broadcast information can be digitized and accessed through a computer by methods known in the art. Modems for receiving information from the Internet are also readily available as computer peripherals. Recently, the infrastructure for wireless communications has developed to the point where cellular base stations and cell phones are commonplace, and wireless transceivers are appearing in many commercial products such as computer peripherals and consumer devices.
In the workplace and in the home, space is not always available to set up a computer with a large display screen. It is desirable to provide a large display screen capability that is easy to deploy, and does not carry the cost burden of a full-scale computer with each display. Thus a display station in the form of a “thin client” would be advantageous, providing a large high-resolution display screen without the bulk and expense of the accompanying computer.
The art of building a spring mechanism into a sunshade to create a retractable shade is well established. The shade can be manually lowered, and then retracted by providing a small additional pull. The additional pull releases a hook mechanism, as will be further described, and allows the internal spring to roll it up. Such shade devices appear in many homes and businesses.
The art of building flexible interconnection circuits is also well known. Methods for assembling packaged parts, IC chips, and surface mount components onto flexible printed circuit boards are known, including the method of flip chip assembly for bare die.
Speech recognition circuits are effective and available for processing a relatively small vocabulary, such as a set of voice commands to an information retrieval system.
A developing art exists for light emitting displays that emit light directly, rather than modulating light from a source such as a backlight. The display back plane includes an array of switching elements provided for controlling light emission at each pixel of the light emitting display. The switching elements can be thin film transistors, TFTs, similar to those employed in liquid crystal display, LCD, panels. Organic light emitting diode, OLED, displays are currently in a rapid state of development. Light emitting polymer, LEP is another name for such displays. Flexible OLEDs or FOLEDs have also been described. Small displays have been integrated into commercial products, and some as large as having 17-inch diagonal screens have been introduced. Most of these displays are bottom-emitting; this means that they are designed to emit light through the substrate, using transparent indium tin oxide as the anode conductor. Top-emitting displays (TOLEDs) have also been described; their light does not pass through the display substrate. These are also referred to as transparent cathode displays. For good color rendition, the substrate for a bottom-emitting display must be transparent and clear. Clear flexible plastic films have been described as substrates for bottom-emitting displays including poly ethylene terepthalate (PET, also known as polyester), and poly ether sulfone (PES). These substrates can be subjected to temperatures as high as 200° C. for brief periods. Accordingly, methods of fabricating TFTs using polysilicon as the semiconductor material have been developed, wherein the substrate temperature does not exceed 200° C. Another approach uses amorphous silicon to fabricate the TFTs. In addition, ink-jet printers have been adapted to precisely dispense tiny spots of organic light-emitting material at each pixel site of an OLED display.